Field of the Invention.
The present invention relates to a continuous form, fill, seal and separate packaging machine. The packaging machine of this invention is uniquely characterized not only by its continuous operation, but also by the means for supplying to the packaging machine an essentially uninterrupted source of web material with which to form and seal the package receptacles.
Description of the Prior Art.
Prior art publications, and particularly issued U.S. Letters Patent, teach a rather large variety of devices for forming, filling and sealing packages. However, as a review of the prior art literature clearly demonstrates, most such packaging machines are of an intermittent operation. That is to say, the web from which the packages are formed generally must stop at each of the work stations of the machine where the forming, filling and sealing operations are accomplished. While the periods of stop, or dwell, are admittedly brief, they nevertheless impose significant limits upon the capacity of such machines for any given period of time.
No doubt in recognition of such limitations, varieties of continuous form, fill and seal devices have been developed and are taught in the prior art. For example, U.S. Pat. No. 3,808,772 discloses an apparatus for continuously forming, filling and sealing containers. According to the disclosure of this patent, continuous movement of the web through the machine is accomplished by providing movable forming, filling and sealing stations. This patent also suggest that filled and sealed containers may be separated from the moving web stop by a similarly movable separating station. Of course, as this patent notes, the movable work stations should preferably be adjusted to operate in push-pull, or out of phase, relationship in which the acceleration of one moving work station in a first direction is offset by the acceleration of another moving work station in a second, opposite direction. Nevertheless, even with an apparatus such as that described in this U.S. Pat. No. 3,808,772, a significant capacity limitation remains in that the total operation of the apparatus must be secured when the web supply is exhausted in order to load the apparatus with a new supply of web stock.
It must, of course, be admitted that prior art means are known for providing a continuous supply of rolled web stock according to various "fly-splicing" devices and methods. Exemplar devices and methods are taught, for example, in U.S. Pat. Nos. 3,886,030; 3,915,399; and 4,363,695. However, all such prior art devices are relatively complex, and require substantial effort to replenish the secondary web stock once it has been spliced onto the exhausted primary stock.
It is therefore clear that there is a great need in the art of packaging machines not only for improved continuous forming, filling, sealing and separating of packages, but also for increasing the efficiency, reliability, and use of operation of the fly-splicing apparatus in order to provide a truly continuous source of web stock material to the packaging machine. These and other objects of the invention will in part be obvious and will in part appear hereinafter.